Abstract
Our search for new metabolites biosynthetically related to fusicoccin with potent plant growth-stimulating activity from the culture filtrate of Fusicoccum amygdali F6 resulted in the isolation of a new derivative of fusicoccin J, as well as fusicoccin J and 16-O-demethyl 3-epifusicoccin J. Its structure was analyzed by 600 MHz NMR spectrometry and identified as 16-O-demethyl fusicoccin J. The biosynthetic relationships among 16-O-demethyl fusicoccin J and its 3-epimer, and fusicoccin J are discussed in connection with the co-occurrence of both of the 3-epimers of 16-O-demethyl fusicoccin J. 16-O-Demethyl fusicoccin J and its 3-epimer showed only low germination-stimulating activity toward lettuce seeds in the presence of abscisic acid (20 μM), the latter being slightly more active than the former.
